The dynamic environmental history and relative sea level (RSL) changes experienced on the Pacific Northwest Coast of North America during the early post-glacial period and the early Holocene resulted in significant visibility challenges for prospection of early coastal archaeological sites. Archaeological visibility is the degree to which cultural material survives post-depositional processes and is detectable on the landscape today. It is influenced by environmental factors such as localized differences in relative sea level change, the rainforest canopy and dynamic post-glacial activity. This study offers an integrated methodological approach for locating palaeo-coastal sites by combining: i) geomorphic interpretation of landscape attributes captured by LIDAR (Light Detection and Ranging) mapping, ii) GIS-based archaeological site potential mapping, and iii) local RSL history. The RSL history for the study site (Quadra Island, British Columbia, Canada) shows notable regression over the past 14 500 years from a highstand of at least 195 m resulting from post-glacial isostatic rebound. Late Pleistocene and early Holocene palaeo-shorelines are found inland from, and elevated above, modern sea level and represent key areas for archaeological prospecting. Bare-earth Digital Terrain Models (DTMs) derived from the LIDAR dataset were interpreted to identify palaeo-shorelines at 10 m and 30 m above modern mean sea level. A GIS-derived map was created to identify regions of high archaeological potential using a decision tree method with variables including distance to palaeo-shoreline, low slope and a coastal complexity parameter. Select geoarchaeological sites were examined in terms of sedimentology, stratigraphy, microfossil content and geochronology as site-specific examples of sea level regression stillstands. Field validation results suggest that this integrated methodology provides a promising approach for archaeological prospection that could be applied to other post-glacial coastal settings. / Graduate

Gerard De Geer was the first one to identify De Geer-moraines, and has since then been mapped by many other studies around the world.  The focus of this study was to examine the environment the ridges form in, regarding the water depth during creation, the importance of topography and the melting rate of the ice. Using airborne Light Detection and Ranging  (LiDAR) data, De Geer- moraines were mapped around eastern Norrbotten county, including Piteå, Boden and Luleå. A total of 14 651 De Geer-moraines were identified over the selected area. Six parameters were analysed during this study; length, orientation, steepness, distance between ridges, current ground level and depth below highest shoreline. In some areas, ridges showed a high, local steepness, while other study sites showed ridges with a varied interconnected form, from straight, to convex and concave. Prominent De Geer-moraines had been identified, where the mean distance between the ridges was calculated to 345 m. Furthermore, other glacial formations (drumlins, flutings, rogen moraines and eskers) showed a relationship to De Geer-moraines, either with a similar angle or a perpendicular relation. A great water depth showed a significant role in the creation of the ridges, with 75% of the identified De Geer-moraines formed in a water depth greater than 150 m. De Geer- moraines found on topographic lows tend to have an interconnected concave form, while over or close to elevated areas; they’re slightly convex. The mean distance between prominent ridges showed a connection to the average retreat rate of the last ice, which suggests that prominent ridges had been formed annually.

La surveillance globale de l’atmosphère et de la pollution de l’air est devenue un enjeu majeur ces dernières années afin d’estimer les conséquences des activités humaines sur notre environnement. Au cours de ces travaux de thèse, l’objectif a été de développer deux instruments LIDARs en détection directe basés sur des émetteurs multi-longueurs d’onde et multi-espèces mettant en œuvre des sources paramétriques optiques innovantes basées sur la technologie NesCOPO (nested cavity optical parametric oscillator) afin de répondre à deux applications : le suivi de la qualité de l’air sur sites industriels et le suivi des gaz à effet de serre depuis l’espace. Un premier instrument multi-espèces a été développé dans le cadre du suivi de la qualité de l’air sur sites industriels, dans la gamme spectrale 3,3 à 3,8 µm, et dédié à des mesures de concentrations moyennes le long de la ligne de visée pour des portées de l’ordre de la centaine de mètres. Une démonstration du potentiel multi-espèces de l’instrument a été réalisée en mesurant simultanément les concentrations en méthane et en vapeur d’eau atmosphériques. A partir d’une source optique existante dédiée à la mesure du dioxyde de carbone seul, un second émetteur multi-longueurs d’onde et multi-espèces a été développé dans une gamme spectrale autour de 2 µm. Son potentiel pour la mesure des gaz à effets de serre depuis l’espace a été étudié En particulier, nous avons démontré que cet émetteur permet de mesurer trois gaz atmosphériques : CO2, H2O et CH4. Une architecture globale d’instrument intégrant cet émetteur a été proposée, afin de réaliser des mesures résolues spatialement, avec des portées de quelques km. De plus, un code de simulation a été développé pour estimer les performances de cet instrument en détection directe. / Atmospheric global monitoring and air quality are major environmental concerns. Global monitoring of some trace and green-house gases would help to understand the consequences of human activities on our environment. The aim of this work is to develop two multi-wavelengths and multi-species direct detection lidar instruments, based on the same laser transmitter baseline approach - an innovative parametric source, the Nested Cavity optical parametric oscilator-and to target two applications: the monitoring of air quality on industrial sites and the monitoring of greenhouse gases from space. The first instrument was designed for industrial plant monitoring applications, in the 3.3-3.8µm, and allows the measurement of multi-species mean concentrations along the line of sight, over a range of around a hundred meters. This instrument was implemented for simultaneous measurements of atmospheric methane and water vapour.The second instrument targets the green-house gases measurement from space applications. In this frame, a new multi-wavelengths and multi-species emitter was developed at 2 µm for space applications. We have demonstrated that this new emitter could address three species: carbon dioxide, water vapor and methane, and studied his potential for space-borne applications.. The architecture of a complete range-resolved instrument based on this transmitter was proposed. Moreover, a numerical algorithm was developed to estimate the instrument’s performances with a direct detection scheme.

Abstract The thesis clearly demonstrates that photon migration measurements allow characterization of pulp and paper properties, especially the fines and filler content of pulp, and the basis weight, thickness and porosity of paper. Pulp and paper are materials with a worldwide significance. Their properties strongly depend on the manufacturing process used. For efficient process control, the employed monitoring and measuring has to be fast. Therefore it is worthwhile to try to develop new approaches and techniques for such measurements. Recent advancements in optics offer new possibilities for such development. If two samples have different optical properties their photon migration distributions are different. The measurement of a photon migration distribution allows some features between two optically slightly dissimilar samples to be distinguished. Some simple measurements, which only yielded the photons' average time of flight, were made with an oscilloscope and a time-of-flight lidar. More precise measurements yielding photon pathway distribution or some selected characteristics like light pulse rise time, broadening, or fall time were measured with a streak camera. Two methods to assess photon path length distribution were introduced: particle determination with simulation, and streak camera with deconvolution. The basic properties for pulp are consistency and fines content and for paper the basic properties are thickness, basis weight and porosity. The influence on photon migration caused by changes in these basic properties was determined. As pulp and paper are rarely very basic, an additional property was demonstrated for both materials. For pulp it was the content of filler talc, and for paper it was the use of beaten pulp as a raw material. These additional properties were also distinguishable.

This thesis describes the work done to implement and develop position and trajectory control of a quadcopter. The quadcopter was originally equipped with sensors and software to estimate and control the quadcopter's orientation, but did not estimate the current position. A GPS module, GPS antenna and a LIDAR have been added to measure the position in three dimensions. Filters have been implemented and developed to estimate the position, velocity and acceleration. Four controllers have been designed that use these estimates: one PID controller and one LQ controller for vertical movement, and a position controller and a trajectory controller for horizontal movement. The position controller maintains a constant position, while the trajectory controller maintains a constant velocity while travelling along a straight line. These position and trajectory controllers calculate the reference angles required to direct the thrust necessary to control the quadcopter's movement. Additionally, an algorithm has been developed to decrease overshoot by predicting future trajectories. These controllers have proven to be successful at controlling the quadcopter's position in all three dimensions, both in practice during outdoor flight and in simulations.

L'érosion hydrique des sols agricoles a pour effet d'augmenter de manière significative la charge de matières en suspension, de nutriments, de pesticides et de pathogènes dans les eaux de surface. Le transport des polluants vers les milieux aquatiques est intimement lié aux processus hydrologiques du bassin versant et plus particulièrement au mécanisme du ruissellement de surface. Les terres agricoles sont particulièrement sujettes à l'érosion hydrique en raison de la faible couverture végétale, notamment dans les cultures annuelles à grandes interlignes, comme la culture de maïs, très répandue dans le sud du Québec.L'avènement des données à référence spatiale de très haute précision de type lidar offre désormais une représentation très fine de la topographie du terrain. Le projet présenté a pour principal objectif de développer des indices spatiaux permettant de mieux cibler les secteurs prioritaires d'intervention relativement aux problèmes de ravinement et de décrochement de berge en milieu agricole. À cette fin, il faut, dans un premier temps, fournir un portrait de l'écoulement de surface à l'échelle du bassin versant, puis poser un diagnostic quant aux caractéristiques du terrain prévalant dans ces zones d'érosion hydrique du bassin versant. Cette analyse spatiale établit les liens statistiques entre la présence et l'importance des marques de ravinement et de décrochement de berge observées et les attributs topographiques et pédologiques du terrain et du cours d'eau. A l'échelle globale, l'indice topographique [lambda] s'est révélé être un indicateur efficace de l'emplacement des secteurs sensibles à l'érosion hydrique, particulièrement le ravinement. A l'échelle de la parcelle agricole, la présence du ravinement s'explique principalement par l'humidité du sol ([lambda] > 8,5) et l'importance du phénomène croit proportionnellement avec la superficie contributive (R[indice supérieur 2] = 0,68). La présence du décrochement de berge est pour sa part clairement liée à la nature des dépôts meubles (texture, érodabilité, perméabilité), à la pente du cours d'eau et à la superficie contributive de la parcelle.L'importance du décrochement de berge s'explique partiellement (R[indice supérieur 2] = 0,38) en fonction de la taille du bassin de drainage de la parcelle, de la hauteur de la berge et de la présence d'une restriction en amont sur le cours d'eau. Des données complémentaires permettraient certainement de mieux comprendre et prédire l'importance des décrochements de berge et des ravinements, notamment des données pédologiques plus précises ainsi que des données décrivant les pratiques culturales et les précipitations.

Atmospheric Boundary Layer (ABL) characteristics can be highly complex; the links between spatial and temporal variability of ABL meteorological quantities and existing land use patterns are still poorly understood due to the non-linearity of air-land interaction processes. This study describes the results from Monin Obukhov similarity theory and statistical analysis of meteorological observations collected by a network of ten Automatic Weather Stations (AWSs). The stations were in operation in the Highveld Priority Area (HPA) of the Republic of South Africa during 2008 – 2010. The spatial distribution of stability regimes as presented by both bulk Richardson number (BRN) and Obukhov length (L) indicates that HPA is dominated by strong stability regime. The momentum and heat fluxes show no significant spatial variation between stations. Statistical analysis revealed localization, enhancement and homogenization in the inter-station variability of observed meteorological quantities (temperature, relative humidity and wind speed) over diurnal and seasonal cycles. Enhancement of the meteorological spatial variability was found on a broad range of scales from 20 to 50 km during morning hours and in the dry winter season. These spatial scales are comparable to scales of observed land use heterogeneity, which suggests links between atmospheric variability and land use patterns through excitation of horizontal meso-scale circulations. Convective motions homogenized and synchronized meteorological variability during afternoon hours in the winter seasons, and during large parts of the day during the moist summer season. The analysis also revealed that turbulent convection overwhelms horizontal meso-scale circulations in the study area during extensive parts of the annual cycle / Dissertation (MSc)--University of Pretoria, 2013. / Geography, Geoinformatics and Meteorology / Unrestricted

LIDAR is the optical equivalent of RADAR. A LIDAR facility has been established at Rhodes University using a flashlamp-pumped dye laser as the transmitter and a photomultiplier tube at the focus of a searchlight mirror as the receiver. The setting up of the receiver and transmitter as well as the design and construction of the photon counting electronics is described. The LIDAR has been used to measure aerosol scattering ratios and temperature profiles in the stratosphere and these results are presented with the algorithms and software used to reduce the data. Finally some recommendations are made for future work

During the 21st century there has been a rapid increase in grid-connected photovoltaic (PV) capacity globally, due to falling system component prices and introduction of various economic incentives. To a large extent, PV systems are installed on buildings, which means they are widely distributed and located close to the power consumer, in contrast to conventional power plants. The intermittency of solar irradiance poses challenges to the integration of PV, which may be mitigated if properly assessing the solar resource. In this thesis, methods have been developed for solar variability and resource assessment in the built environment on both national and local level, and have been applied to grid integration studies. On national level, a method based on building statistics was developed that reproduces the hourly PV power generation in Sweden with high accuracy; correlation between simulated and real power generation for 2012 and 2013 were 0.97 and 0.99, respectively. The model was applied in scenarios of high penetration of intermittent renewable energy (IRE) in the Nordic synchronous power system, in combination with similar models for wind, wave and tidal power. A mix of the IRE resources was sought to minimise the variability in net load (i.e., load minus IRE, nuclear and thermal power). The study showed that a fully renewable Nordic power system is possible if hydropower operation is properly planned for. However, the contribution from PV power would only be 2-3% of the total power demand, due to strong diurnal and seasonal variability. On local level, a model-driven solar resource assessment method was developed based on low-resolution LiDAR (Light Detection and Ranging) data. It was shown to improve the representation of buildings, i.e., roof shape, tilt and azimuth, over raster-based methods, i.e., digital surface models (DSM), which use the same LiDAR data. Furthermore, the new method can provide time-resolved data in contrast to traditional solar maps, and can thus be used as a powerful tool when studying the integration of high penetrations of PV in the distribution grid. In conclusion, the developed methods fill important gaps in our ability to plan for a fully renewable power system.

The Florida Keys is one of the most susceptible island chains in the United States to sea level rise induced inundation because most elevations are lower than 2 m above current sea level. By analyzing a digital elevation model (DEM) derived from airborne light detection and ranging (LiDAR) measurements using a geographic information system (GIS), this paper estimates the potential impacts of a series of sea level rise scenarios from 0.15 to 5 m on the Florida Keys. The results showed that a 0.5 m sea level rise by the end of this century would inundate a large area, about 66% of the total area of the Florida Keys. However, this extent of sea level rise would not inundate a large percentage of the current population (<9%) and property (<14%). In contrast, a 1.5 m rise in sea level would inundate 90% of the land and 70% of population and property in the Florida Keys. Comparison of inundation dynamics using hypsometric curves demonstrated that, among the major Keys population centers. Big Pine Key is most susceptible to sea level rise, followed by Key Largo and Key West. Thus, inundation dynamics need to be considered in policy-making.